Using proper method to solve X & # 178; - 8x = 20 （2） 2x²-6x-1=0 (3) Root sign 2x & # 178; - 4x = 4 root sign 2 （4）（x-2)²-4(x-2)=-4

Using proper method to solve X & # 178; - 8x = 20 （2） 2x²-6x-1=0 (3) Root sign 2x & # 178; - 4x = 4 root sign 2 （4）（x-2)²-4(x-2)=-4

（1）x²-8x=20
x²-8x-20=0
(x-10)(x+2)=0
X = 10 or x = - 2
（2）2x²-6x-1=0
x²-3x=1/2
x²-3x+(3/2)²=1+(3/2)²
(x-3/2)²=13/4
x-3/2=±(√13)/2
X = (3 + √ 13) / 2 or x = (3 - √ 13) / 2
(3) Root sign 2x & # 178; - 4x = 4 root sign 2
x²-2√2x=4
x²-2√2x+(√2)²=4+(√2)²
(x-√2)²=6
x-√2=±√6
X = {2 +} 6 or x = {2 -} 6
（4）（x-2)²-4(x-2)=-4
（x-2)²-4(x-2)+4=0
(x-2-2)²=0
(x-4)²=0
x=4

The process of √ X & # 178; - 8x-16 = x-4

Original = | 1-x | - radical (x-4) ^ 2
The answer is 2x-5, it is not difficult to see that X-1 - (4-x) = 2x-5
That is to say, | 1-x | = X-1 radical (x-4) ^ 2 = 4-x
So 1-x=

What is the X of X & # 178; - 8x-20 = 0?

(x+2)(x-10)=0
The solution is x = - 2 or x = 10